Studies have been conducted on the application of polyhedral structure-containing polysiloxane compounds having various types of functional groups to electronic components and semiconductor components and the like since the transparency of their resulting cured products is high and they are materials having high reliability such as favorable heat resistance and light resistance (see, for example, Patent Documents 1 to 4).
One example of applications of these materials is a resist material. Various polysiloxane-based materials have been used for this application in the past. When the above-mentioned polyhedral structure-containing polysiloxane compounds having high reliability is applied, it is necessary to impart alkali solubility.
A method comprising introduction of organic acid groups is known as a typical method for imparting alkali solubility. However, this method has a potential problem of causing decreases in the heat resistance and light resistance inherently possessed by polyhedral structure-containing polysiloxane compounds, along with introduction of organic acid groups.
On the other hand, examples of patterning materials that have conventionally been used as alkali-developable resist materials include resins having acidic groups such as novolak resin, acrylic acid copolymers and polyamide acid (see, for example, Patent Documents 5 to 7).
However, in processes in which these resins are exposed to high temperatures such as during electronic component mounting, they lack reliability (in terms of, for example, thermal decomposition, cracking and separation) and transparency at high temperatures, and are unable to satisfy requirements.
In the field of thin film transistors (TFT) widely used to drive liquid crystal displays (LCD) and the like, oxide semiconductor and organic semiconductor materials are attracting attention and being actively researched and developed as next-generation transistor technologies. This is because semiconductor layers can now be formed at low temperatures and by easier methods such as printing methods and therefore TFT may be expanded into flexible displays and the like. In order to form these next-generation transistors, technologies and materials are being earnestly sought that similarly allow the formation of insulators at low temperatures and using a simple solution process. In this field as well, if alkali-developable materials can be used for the insulators, it will offer the advantage of simplifying contact hole formation and other patterning. On the basis of this background, gate insulators for organic TFT have been attempted to be formed from organic materials such as polyvinyl alcohols, epoxy resin or silicon-based polymers. However, gate insulators using these organic materials have inferior insulating properties in comparison with inorganic insulators obtained by CVD, and an effective insulator material has yet to be obtained that allows low-temperature formation.
Patent Document 1: Japanese Patent Application Laid-open No. 2004-359933
Patent Document 2: Japanese Patent Application Laid-open No. 2004-143449
Patent Document 3: Japanese Patent Application Laid-open No. 2006-269402
Patent Document 4: Japanese Patent Application Laid-open No. 2005-23256
Patent Document 5: Japanese Patent No. 3203843
Patent Document 6: Japanese Patent Application Laid-open No. 2005-266673
Patent Document 7: Japanese Patent Application Laid-open No. H4-218051
Patent Document 8: Japanese Patent Application Laid-open No. 2004-349319
Patent Document 9: Japanese Patent Application Laid-open No. 2007-158147
Patent Document 10: Japanese Patent Application Laid-open No. 2007-43055